Let’s talk about generators, so I assume you’re looking into generators for your off-grid energy system and you’ve seen that there’s a distinct difference between an unfettered type of generators and the conventional generators, that the inverter types come at a significant price increase, though the salespeople and the brochures will tell you that they also come with a lot of advantages and that they are worth spending extra money on it.
The question is to which accent is this just fancy sales talk and what kind of real life advantages can you expect when you’re operating the inverter types?
And therefore, is it worth spending your money on that?
My goal in this article is to provide you with an overview of the facts regarding inverter versus conventional generator technology and kind of poke through the marketing stories around them. And I want to make sure that you have the relevant information that you need in order to make the best decision for whichever generator is best for your setup. Before we go ahead, let me introduce myself.
My name is Ben Laaerberg from My Next Generator. I am a renewable energy engineer and I’m specialized in battery based off grid solar energy systems. I have run companies and a design and installation of these set ups. I’ve held the position of energy officer for the United Nations and I founded a company Solar Solution, for which I share my knowledge and expertise through articles such as this one seminar’s online articles and through direct personal support for services on my website.
So in order to keep this article brief and focused, I’ll cut it up into four sections or first look at the generator. Basics will then compare the inverter versus the conventional type. Generators will briefly look at the different fuel source options that you have. And I’ll wrap up with conclusions and a few specific tips for you. So let’s start by looking at the generator basics.
I’m going to try to explain this to you in less than a minute. So it started with this Englishman called Michael Faraday in 1831. He figured out something which is now referred to as Faraday’s law. So basically what it says is that if you take a magnetic field and something that conducts electricity, such as copper wire and you move the copper wire through the magnetic field, you have created an electric generator which makes electricity at a different kinds of electrical generators, such as the ones that produce alternating current referred to as alternators.
You can find them in your car, for example, or the ones that produce direct current dynamos. You can find them in portable devices such as radios that you have to hand crank or flashlights. Now, those are the basics of generators, and I think I managed to do it in less than six seconds. Right. So let’s move ahead and actually start comparing the inverter for the conventional type of generator.
And I’d like to start by looking at the conventional type first, that this type typically consist of an internal combustion engine that is driven by whichever kind of fuel source. And this then coupled to the actual electrical generator and the two of them together we refer to as the generator or the genset result of the two components still being kind of separate is that the whole unit together can be relatively heavy or bulky.
So I want to explain to you the difference in quality of electricity produced by a conventional generator and an inverted generator. And I’m going to try to do that by drawing an analogy between making electricity and making Frys. So the conventional generator is trying to produce high quality electrical output. It’s a perfect French fries by, for example, controlling the engine speed and therefore the frequency or the Durnan magnetic field and therefore the output voltage and on average is doing a pretty good job.
But whenever you’re changing something to the loads on the generator, such as by turning on or off your air conditioning or your cooker or whatever, you can hear that change in sound like me. And so whenever that happens, you are actually not making perfect French fries, but for a short period of time, you’re making kind of messy, uneven potato wedges. Right. So just remember this analogy and I’ll get back to it later on when I, compared to the inverted, generate.
Other things I’d like to mention is that, yes, they can be fairly noisy because they run at the same speed all the time. But it’s also important to realize that you get the best fuel efficiency out of them. If you run them at full load, if you run the generator at 50 percent of its load or less, you can spend twice the amount of fuel per amount of electricity produced compared to when it’s under full load.
So real life numbers that you can expect is that generate under full load will cost you around 50 cent per unit of energy produced compared to a generator on a lower load because you around a dollar per unit of electricity produced. So now let’s look at the inverter generator. So the basic layout is somewhat similar to the conventional type.
But now what they’ve done that instead of having a separate engine and a separate electrical generated a really combine it into one unit. So they do this, for example, by using the flavor of the engine and then using it to directly produce electricity. So the obvious result of this is that the overall weight of the unit, the volume can be drastically reduced. So now let’s look at how the electricity is being produced, how the quality is being controlled.
So this is where we get back to. The French fry stopping the inverted generator takes the power produced, mashes it up the mashed potatoes, and then produces this perfect French fries.
It takes the AC power being produce, breaks it down to D.C. power and then through an inverter, builds it up to AC power again. Therefore, your output is very controlled, very stable. A perfect sign is waveform frequency output, voltage, high quality electricity, perfect French fries. So because of this, the inverted generator can run at lower speeds and therefore being less noisy.
And if you run it at lower speeds, at lower loads, the fuel efficiency will be somewhat similar to the fuel efficiency when running it at higher loads. So now the results of all of this is that an inverted generator can run at a lower engine speeds while still providing with high quality power. Because you can run it at lower engine speeds. It can be less noisy. If you’re running it at lower engine speeds, your fuel efficiency will be still somewhat similar to then when you’re running it at full load.
So let’s briefly look at a different kind of fuel that you could consider it. Three different ones. Basically, you’ve got your diesel, you’ve got your petrol, gas, gasoline, whatever you call it. And the third one is LBG, bottled gas, propane, or refer to the same thing. The energy density of diesel is slightly higher than that of petrol. And because diesel engines burn fuel more efficiently, you can typically expect a 20 to 30 percent reduction in the price that you pay per unit of electricity produced.
The energy density of propane is significantly lower than that of gas. And often when you look in the details, which actually will pay for your propane, if you’re using the conventional bottle exchange services, is that you’ll end up paying twice as much per unit of electricity produced when you compare using propane versus conventional gas or petrol.
Also, if you’re externalities I would like to mention, such as propane burns and handles use a lot cleaner than the liquid fuels that the liquid fuels of a higher energy density. So you need less storage space and diesel engines. They require higher upfront investments. They’re heavier and noisier, but their service life is just really amazing if you compare it to gasoline engines. So this brings us to the conclusion and deps.
I’ll give you four conclusions and two tips. So conclusion number one is that, yes, definitely inverted generators will give you a great advantage over the conventional generators when you’re looking at the fuel cost under varying loads, which links directly to the second conclusion, which is that if you’re using your inverted generator on the fallout, you’re comparing it to a conventional generator on the float.
Then they produce kind of the same amount of noise. They consume the same amount of fuel. It’s just that the inverter generator can possibly produce a little bit higher quality of electrical output. The third one is that for inverter generators, due to the integration of components, their weight is definitely less than the conventional generators.
And number four is that operating your generator on bottled gas is due to the higher prices, still less cost efficient when compared to running into unconventional petrol. So my first step is that if you’re using an inverted generator, you have turned off the eco throttle mode, then you’ve basically reduced its functionality to that of a conventional generator and you’ve lost all the advantages that come with an inverted type of generator.
The second tip is that if you haven’t made up your mind what you want to go for inverter, a conventional type of generator, if you know that you’ll be using a generator on a full load and the loads will be fairly constant, you know, they’ll perform basically the same. So you might want to consider not paying the premium for the inverter type of generator, which will basically do the same as the conventional type generator. So now a question for you.
If there’s something that I haven’t covered yet and that you’d like to learn more about, let me know in the comments below. And I’ll use this as inspiration to provide more articles for you and for others. Of course, you’ve got all the great options of sharing, liking, subscribing, etc.. I really hope you enjoyed this article and I’ll see you in the next one.